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981.
A. I. Maksimov 《Thermophysics and Aeromechanics》2007,14(4):469-492
The paper briefly describes the life and activities of F.A. Zander and Yu.V. Kondratyuk (A.I. Shargei), pioneers of domestic
rocket engineering who made a significant contribution to the development of cosmonautics and rocket technologies. The main
ideas and proposals of these prominent scientists and inventors in the field of rocket and space engineering, which found
their application in space conquering, are considered.
To the 120th anniversary of F.A. Zander and 110th anniversary of Yu.V. Kondratyuk 相似文献
982.
Magnetism of Fe/Cr/Sn/Cr multilayers have been studied by the first-principles density-functional theory. Calculations by the full-potential linearized augmented plane waves (FP LAPW) and screened Korringa–Kohn–Rostoker (SKKR) methods have shown that two types of solutions may be found in these systems: a high-spin (HS) and a low-spin (LS) ones in accordance with the Cr magnetic moment magnitudes. In this work, we have concentrated our attention on the LS solution. The calculation has shown that the LS solution has a phase slip of antiferromagnetic ordering in Cr and is classified as an incommensurate spin density wave (ISDW). The dependence of the ISDW solution on the thickness of Cr, lattice parameter and boundary conditions has been investigated. 相似文献
983.
The dispersion relation of magnetostatic waves tangentially magnetized to saturation ferrite film, with a “magnetic wall” condition (tangential component of microwave magnetic field is equal to zero) on one of the film surface and with a metal condition on the opposite surface is analyzed. The dispersion characteristics show that unidirectional magnetostatic waves appear in this structure: they can transfer energy in one direction only and fundamentally cannot transfer energy in the opposite direction. The dispersion-free propagation of magnetostatic waves also is possible in the structure in a wide frequency interval. 相似文献
984.
N. V. Timofeeva 《Mathematical Notes》2007,82(5-6):677-690
A new compactification of the variety of moduli of stable vector 2-bundles with Chern classes c 1 and c 2 is constructed for the case in which the universal family of stable sheaves with given values of invariants is defined and there are no strictly semistable sheaves. The compactification is a subvariety in the Hilbert scheme of subschemes of a Grassmann manifold with fixed Hilbert polynomial; it is obtained from the variety of bundle moduli by adding points corresponding to locally free sheaves on surfaces which are modifications of the initial surface. Moreover, a morphism from the new compactification of the moduli space to its Gieseker-Maruyama compactification is constructed. 相似文献
985.
V. V. Zudilin 《Mathematical Notes》2007,81(3-4):297-301
We prove two new series of Ramanujan type for 1/π2. 相似文献
986.
Based on the matrix-analytic approach to fluid flows initiated by Ramaswami, we develop an efficient time dependent analysis
for a general Markov modulated fluid flow model with a finite buffer and an arbitrary initial fluid level at time 0. We also
apply this to an insurance risk model with a dividend barrier and a general Markovian arrival process of claims with possible
dependencies in successive inter-claim intervals and in claim sizes. We demonstrate the implementability and accuracy of our
algorithms through a set of numerical examples that could also serve as test cases for comparing other solution approaches.
相似文献
987.
I. P. Rochev 《Mathematical Notes》2007,81(1-2):247-259
We consider generalizations of Pólya’s theorem to the case of entire functions taking algebraic values at natural or integer points. 相似文献
988.
S.G. Li G. Fu I. Reading S.B. Tor N.H. Loh P. Chaturvedi S.F. Yoon K. Youcef-Toumi 《Applied Physics A: Materials Science & Processing》2007,89(3):721-728
Micro powder injection molding (μPIM) is one of the potential processes for the mass production of metallic microstructures
and micro components. Here, μPIM is the miniaturization of conventional PIM, which involves four processing steps: mixing,
injection molding, debinding and sintering. This paper looks into the feasibility and effectiveness of μPIM as a key mass
production process for the fabrication of metallic micro components. For it to be an effective re-production process, it is
imperative to examine how well parts can be duplicated/fabricated from a master mold. In this work, the dimensional variation
of high-aspect-ratio micro-pillars arrays, in particular the dimensional shrinkage, global warpage, and surface roughness
at each stage of the μPIM process for a range of molding pressures, are quantified and compared in detail. The sensitivity
of the dimensional variation of the microstructures to the packing pressure is reported. The mechanism behind the dimensional
variation is analyzed.
PACS 81.20.Ev; 81.20.Hy; 81.70.Fy; 07.60.Ly; 81.05.-t 相似文献
989.
E. K. Sadykov V. V. Arinin G. I. Petrov A. V. Pyataev F. G. Vagizov O. A. Kocharovskaya 《Hyperfine Interactions》2006,167(1-3):893-896
The role of quantum interference (QI) in spectra of the resonant Mössbauer scattering is investigated. As a mechanism ensuring the QI conditions, the radio-frequency (RF) mixing of the spin sublevels of the excited nuclear state is considered. It is shown that QI leads to a significant intensity redistribution of the elastic and Raman scattering. 相似文献
990.